Millions of years of evolution has fine tuned the human brain to use it's most primitive parts to take decisions in split seconds. The limbic brain along with your emotions are hugely powerful when it comes to your decision making capabilities and probably the only reason why you are alive today reading this blog. When the lion roars or when a huge mass of iron and steel on wheels is moving towards you at 60 miles an hour, your limbic brain is what causes you to run and saves you from becoming lion lunch or the subject of a car accident. The emotional system of our brain is much more powerful at making decisions than what most of us realize and give it credit for. Countless books have been written on this topic but if there is one book that brings a lot of the research on the topic together it is How We Decide by Jonah Lehrer.

John Describes the power of how important intuitions can be:

Riley had been on duty since midnight. At 5:01 in the morning, just as the Allied ships began shelling Ash Shuaybah, he noticed a radar blip off the Kuwaiti coast. A quick calculation of its trajectory had it heading straight for the convoy. Although Riley had been staring at similar-looking blips all night long, there was something about this radar trace that immediately made him suspicious. He couldn't explain why, but the blinking green dot on the screen filled him with fear; his pulse started to race and his hands became clammy. He continued to observe the incoming blip for another forty seconds as it slowly honed in on the USS Missouri, an American battleship. With each sweep of the radar, the blip grew closer.

It was approaching the American ship at more than 550 miles per hour. If Riley was going to shoot down the target—if he was going to act on his fear—then he needed to respond right away. If that blip was a missile and Riley didn't move immediately, it would be too late. Hundreds of sailors would die. The USS Missouri would be sunk. And Riley would have stood by and watched it happen.

But Riley had a problem. The radar blip was located in airspace that was frequently traveled by American A-6 fighter jets, which the U.S. Navy was using to deliver laser-guided bombs to support the Marine ground invasion. After completing their sorties, the planes flew down the Kuwait coast, turned east toward the convoy, and landed on their aircraft carriers. Over the last few weeks, Riley had watched dozens of A-6s fly a route nearly identical to the one being followed by this unidentified radar blip. The blip was also traveling at the same speed as the fighter jets and had a similar surface area. It looked exactly like an A-6 on the radar screen.

The target was moving fast. The time for deliberation was over. Riley issued the order to fire; two Sea Dart surface-to-air missiles were launched into the sky. Seconds passed. Riley nervously stared at the radar screen, watching his missiles race toward the object at speeds approaching Mach 1. The blinking green blips appeared to be drawn to the target, like iron filings to a magnet. Riley waited for the interception.

The explosion echoed over the ocean. All of the blips immediately disappeared from the radar screen. Whatever had been flying toward the USS Missouri helplessly fell into the sea, just seven hundred yards in front of the American battleship. A few moments later, the captain of the HMS Gloucester entered the radar room. "Whose bird is it?" he asked Riley, wanting to know who was responsible for destroying the still unidentified target. "It was ours, sir," Riley responded.

The captain asked Riley how he could be sure he'd fired at an Iraqi missile and not at an American fighter jet. Riley said he just knew.

John in his book goes on to describe how an excruciating investigation later goes on to conclude that Riley had indeed taken the correct decision and how Gary Klein a cognitive psychologist, later dissects what was going on in Riley's head when he took the call of shooting down the missile:

Klein was intrigued. He had spent the last few decades studying decision-making in high-pressure situations, and he knew that intuition could often be astonishingly insightful, even if the origin of those insights was obscure. He was determined to find the source of Riley's fear, to figure out why this particular blip had felt so scary. So he went back to the radar tapes.

He soon realized that Riley had gotten used to seeing a very consistent blip pattern when the A-6s returned from their bombing sorties. Because Riley's naval radar could pick up signals only over water—after a signal went "wet feet" he was accustomed to seeing the fighter jets right as they flew off the Kuwaiti coast. The planes typically became visible after a single radar sweep.

Klein analyzed the radar tapes from the predawn missile attack. He replayed those fateful forty seconds over and over again, searching for any differences between Riley's experience of the A-6s returning from their sorties and his experience of the Silkworm blip.

That's when Klein suddenly saw the discrepancy. It was subtle, but crystal clear. He could finally explain Riley's intuitive insight. The secret was the timing. Unlike the A-6, the Silkworm didn't appear off the coast right away. Because it traveled at such a low altitude, nearly two thousand feet below an A-6's, the signal of the missile was initially masked by ground interference. As a result, it wasn't visible until the third radar sweep, which was eight seconds after an A-6 would have appeared. Riley was unconsciously evaluating the altitude of the blip, even if he didn't know he was doing it.

This is why Riley got the chills when he stared at the Iraqi missile on his radar screen. There was something strange about this radar blip. It didn't feel like an A-6. Although Riley couldn't explain why he felt so scared, he knew that something scary was happening. This blip needed to be shot down.

The book is a fascinating read not just because it showcases how powerful our emotions can be in taking decisions, it also showcases when our emotions can lead us astray and provides real pragmatic advice on how to balance the emotional with the thinking parts of our brains to come up with better decision making capabilities.

The book itself is one of the better books on the human brains that I've read and I personally loved the book. However, what was disheartening was learning that the book has been withdrawn from the market by publishers after the discovery of the fact that Lehrer had fabricated quotes used in his books. I would have personally quoted this book left right and center in my discussions with people, had it not been for the nagging doubt I have about the authenticity of every minute detail the book goes into. The author has been found guilty of fabricating facts and plagiarism but that still doesn't take away the fact that the book is a nice read and provides valuable insights that I never had before. I give this book a 4 on 5 and would definitely recommend this book to anyone who is interested in a deeper insights on what our brain is doing when it's indulging in the act of taking decisions.